RAID (Redundant Array of Independent Disks) with built in redundancy suggests that there is a level of data security, protecting against a failure, but it is still important to that you have a backup strategy in place, as well as a disaster recovery plan. Business continuity is extremely important, and any complacency will at some point usually lead to a loss of data. Part of a good business continuity plan should include a RAID data recovery option to give peace of mind when a disaster occurs.
It is often thought that having a RAID with parity stripes or mirroring will protect against the chances of data loss, but this only serves as protection to a certain point. It is possible, even with mirroring for a situation to occur whereby data loss can happen.
Hard Disk Drive Failures
Hard disk drives installed into a RAID array are often purchased from the same supplier and from the same production batch. They are then inserted into the RAID server cabinet which keeps them in the same operating environment, leading to them all having a similar failure rate and lifespan.
Hard disk drives start to accumulate errors, with bad sectors swapped out, until the grown defect list is exhausted, at which point they will be detected by the RAID array, which requires the drive to be replaced and the RAID rebuilt. Once a drive fails, the chances that another drive in the array will also suffer a failure is quite high, so it’s important that the RAID array is not allowed to run in degraded mode as this puts all the data at risk.
Rebuilding the RAID Array
Attempting to rebuild a RAID array should only be undertaken by experienced professionals, with the full knowledge and understanding of RAID array architecture. Allowing someone with limited or no experience could potentially risk causing further damage, leading to problems should RAID data recovery be required.
It is important that when a rebuild is attempted, that the drive removed from the RAID array is labelled, so that should a total RAID failure occur, it is clear exactly which drive is the original. With the size of hard disks increasing, a complete rebuild takes a considerable amount of time, during which any bad sectors found on any of the other drives, or the mirror copy, will cause the process to fail.
RAID Data Recovery
If your RAID fails, particularly during a rebuild, it is important to down the server and not attempt any more actions, as these could result in further damage occurring. The best decision is to contact a professional RAID data recovery company with the experience and expertise to be able to recover your data files, no matter which RAID configuration or file systems it contains.
Our RAID recovery specialists at DiskEng have vast experience in recovering data from all types of RAID array and the file system which may be contained on them. It is important to know that you can trust the experts when it comes to recovering the critical files from your RAID array server following a failure